As a conventional door with a door closer of this type, the applicant already disclosed it in Patent applications: Japanese Patent Application No. 2005-308456 and No. 2005-356164.
In Japanese Patent Application No. 2005-308456, the door with a door closer is arranged such that by providing with a delay mechanism including such as a planetary gear unit(s), a spiral spring(s) to the door closer, the door is automatically closed after the elapse of a certain time since the door was opened.
In the mean while, in Japanese Patent Application No. 2005-356164, the door with a door closer is arranged such that by providing a delay mechanism including such as a solenoid(s), timer(s) with the door closer, the door is automatically closed after the elapse of a certain time since the door was opened.
The aforementioned Japanese Patent Application No. 2005-308456 and No. 2005-356164 both disclose a door closer, which can lock the door when the door was opened and release the door after the elapse of a certain time, thereby automatically closing the door.
In particular, Japanese Patent Application No. 2005-356164 discloses a door closer, which can be fabricated simply and cheap in addition to the aforementioned effects.
However, since the aforementioned door closers both are provided the delay mechanism with them, there may be a problem in the appearance by means of providing the delay mechanism with the door closer; in other case that the door closer is embedded inside the door, wall, or the ceiling, as well as under the floor and thereby being not exposed, there may be a difficulty in providing the delay mechanism with the door closer.
Considering the aforementioned present situation, the object of the present invention is to provide with a delay unit for door with a door closer, door closer with a delay unit, and door with a door closer having a delay unit, which can automatically close the door after the elapse of a certain time since the door with a door closer was opened and be installed in the case that the door closer is embedded inside the building, thereby being not exposed.